A 25-year NFL study found running backs’ fumble rates tend to regress toward the average; its author expects James Cook’s rate to fall eventually. Since 2025, Cook has averaged 2.01 fumbles per 100 touches and fumbled eight times in his last 14 games, including playoffs.
The analysis used regular-season nflverse play-by-play data from the 2001 season through 2025 and included running backs with at least 100 touches. Year-to-year fumble-rate correlation was 0.197. The most fumble-prone fifth of backs dropped from a 2.17% rate to 1.24% the next season; the least-prone fifth rose from 0.08% to 0.83%.
Cook’s career fumble rate, counting postseason, is 1.25 per 100 touches; before 2025, it was 0.80 during his first three seasons with Buffalo. The author says the recent rate cannot be dismissed as random but does not know when any regression will begin.
